New poly(amide-imide)s syntheses. XXIII. Synthesis and properties of poly(amide-imide)s derived from 4,4 '-[1,4-phenylenebis(isopropylidene-1,4-phenyleneoxy)]dianiline and various bis(trimellitimide)s

A series of poly(anmide-imide)s IIIa-m containing flexible isopropylidene a nd ether groups in the backbone were synthesized by the direct polycondensa tion of 4,4'-[1,4-phenylenebis(isopropylidene-1,4-phenyleneoxy)]dianiline ( PIDA) with various bis(trimellitimide)s IIa-m in N-methyl-2-pyrrolidone (NM P) using triphenyl phosphite and pyridine as condensing agents. The resulti ng poly(,amide-imide)s had inherent viscosities in the range of 0.80-1.36 d L/g. Except for those from the bis(trimellitimide)s of p-phenylenediamine a nd benzidine, all the polymers could be cast from DMAc into transparent and tough films. They exhibited excellent solubility in polar solvents. The 10 % weight loss temperatures of the polymers in air and in nitrogen were all above 495 degrees C, and their T-g values were in the range of 201-252 degr ees C. Some properties of poly(amide-imide)s III were compared with those o f the corresponding poly(amide-imide)s V prepared from the bis(trirmellitim ide) of diamine PIDA and various aromatic diamines. (C) 1999 John Wiley & S ons, Inc. J Polym Sci A: Polym Chem 37: 69-76, 1999.